This paper examines the cost of electricity shortages on the Nigerian manufacturing sector. Utilizing the data obtained from a 1998 nationwide survey, the paper details the various costs from power outages and examines the response of manufacturers to the infrastructure problem. The findings of the study confirm that the cost of electricity failures on the Nigerian manufacturing sector is quite high. Firms incur huge costs on the provision of expensive back-up to minimise the expected outage costs. The average costs of this back-up are on the average 3 times the cost of publicly supplied electricity. The marginal cost estimates also indicate that the cost of kWh of unserved electricity in Nigeria is very high. Small-scale firms bear the greater proportion of the cost of the power failure. A situation where firms spend as much as 20-30% of initial investment on the acquisition of facilities to enhance electricity supply reliability has a significant negative impact on costs competitiveness of the manufacturing sector. Thus, the study supports current government efforts to privatise the public monopoly and liberalizes the electricity market. These hopefully will mitigate the burden of poor power supply as well as introduce the needed competition into the electricity market in the country. (C) 2003 Elsevier Science Ltd. All rights reserved.